The present invention relates to a dish-shaped container made of a folded cardboard blank sealable on both sides, comprising a rectangular-shaped bottom and four upfolded lateral panels, which are connected to the container corners by a plurality of essentially triangular corner panels. An outer circumferential flange parallel to the bottom is predominantly double-walled, and essentially formed from first and second outer strips. The first outer strips are folded onto the respective lateral panels, and the second outer strips, folded onto the first outer strips, are aligned with their cut edges towards the outer surface of the respective lateral panels.
U.S. Pat. No. 4,998,669 discloses a container which has a reinforced outer flange, so that even in the case of very thin cardboard, the container is sufficiently stable, whereby this outer flange extends parallel to the bottom. Thereby, the container can be closed by a flat membrane or a paper sheet. A disadvantage of this approach is, however, that neither the first nor the second outer strips extend over the corner panels, on which only very narrow supporting panels are folded. The indentations of the cardboard blanks extending to the filler space lead to the closed container not always being sufficiently impermeable at the container corners.